In a statement on the club’s website, the owner, Rinat Akhmetov, warned the players that “in the first instance they will suffer” if they do not return, because their actions could activate compensation clauses forcing them to pay “tens of millions of euros” to Shakhtar.

“It is true, six team players have not come,” said Akhmetov.

“I don’t rule out that these players will return to the team quickly, and some of them tomorrow. Players have contracts that they have to abide by. If they do not come, I think, they will be the first to suffer. Each of them has a minimum release clause, which is tens of millions of euros. If someone wants to reduce this amount by a million, then such a decision is our right. There won’t be a clearance sale.

“Hopefully, the mind and heart will prevail over misunderstanding, and the players will not follow temptation and fear. Especially since there is nothing to fear. We are ready to provide security. We will not take risks and in any case we won’t bring players to dangerous places.”

Shakhtar’s Romanian coach Mircea Lucescu has blamed British-based agent Kia Joorabchian for persuading the players not to return to Ukraine.

“It is necessary to explain what happened,” he said on Shakhtar’s website. “It is not the players’ desire, it’s their agents’ work. A few hours before the kickoff of the match against Lyonnais, Kia showed up. And after the game, at two in the morning, he took our players away. The very talented ones: Teixeira, Douglas, Fred. The rest are not so important.

“He wanted to do the same to Adriano, Ilsinho, Marlos and Taison. But they refused. His goal is to make the players free agents, just to make money. This is wrong. This is his alibi. He wants to make use of the situation in the country and get the players for free. But they have contracts. Ferreyra has another agent. But he also expects to capitalise on the situation.”

The Ukrainian military is attempting to retake the city of Donetsk in the east of the country, which is controlled by pro-Russian rebels. The Ukrainian Football Federation has yet to rule where Shakhtar will play its home games while the conflict rages.

“We want to play in Donetsk very much, but, unfortunately, at the moment we cannot do it,” said Akhmetov.

“We will play where we will be allowed to: we would like to do it in Kharkiv. The decision regarding the championship is taken by the Ukrainian Football Federation. Through our game, we will call for peace and try to bring joy to our fans.”

Manchester United have been linked with an approach for forward Douglas Costa, who has scored 33 goals in 170 appearances for Shakhtar since 2010. Brazilian international Fernandinho left Shakhtar last summer for Manchester City.